This project compares the clinical outcomes and resource requirements of two alternative protocols for the use of dental pit-and-fissure sealants. Pit-and-fissure sealants are often placed on the fissured surfaces of newly-erupting permanent molars, in an effort to ensure that decay will not begin on those surfaces. Because of the decline in dental caries in the US and many other countries, a growing proportion of the surfaces that are sealed in this way may not develop caries, even without the sealants. There is concern that the placing of sealants on an ever-increasing number of teeth that may not decay constitutes unnecessary treatment and an inappropriate use of resources. The project compares the approach of sealing sound teeth to one which uses sealants only as a non-invasive, conservative intervention on incipient lesions, but does not place sealants on sound teeth. The result of this research will provide the necessary information to allow cost-effective use of this highly efficacious procedure. The two protocols are being compared in a prospective clinical trial. One randomly-assigned group of children is being treated according to the protocol which encourages the use of sealants on sound fissured surfaces. The other randomly-assigned group receives sealants only on suspected incipient lesions. A total of 1,000 children are being enrolled over a three-year period, and will be followed for an additional two years, in order to evaluate the clinical outcomes and resource requirements for the two alternatives.